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The time-temperature-property (TTP) and the time-temperature-transformation (TTT) curves of 7097 aluminum alloy are determined by interrupted quenching experiments in order to investigate the quench sensitivity. The quenching sensitive zone is 230°C-370°C, and the nose temperature and transformation time are about 320°C and 1.2 s, respectively. The evolution of quench-induced precipitates during different isothermal temperatures treatment has been observed by the transmission electron microscope. The number and size of quench-induced precipitates are gradually increased with the extension of isothermal holding time. Moreover, the quenching sensitivity of 7097 aluminum alloy is lower than that of 7055 aluminum alloy and 7050 aluminum alloy, but higher than that of 7085 aluminum alloy, and the influence of alloy composition on the quenching sensitivity is investigated.

The aim of this study was to predict the yield strength of as-quenched aluminum alloys according to their continuous quench cooling path. Our model was established within the framework of quench factor analysis (QFA) by representing a quenching curve as a series of consecutive isothermal transformation events and adding the yield strength increments after each isothermal step to predict the yield strength after continuous quench cooling. For simplification; it was considered that the effective hardeners during quenching were the nanosized solute clusters formed at low temperatures, whereas the other coarse precipitates were neglected. In addition, quenching tests were conducted on aluminum plates with different thicknesses. The predictions were compared with the experimental measurements, and the results showed that the predictions fit the measurements well for the 40-and 80-mm-thick plates but overestimated the as-quenched yield strength at the mid-thickness of the 115-mm-thick plates.